Lock mechanism

ABSTRACT

A lock mechanism mounted in a casing including a bolt member slidably mounted in the casing for movement between lock and unlock positions. A plurality of latch levers and at least one master lever are pivotally mounted in the casing by means of a pivot pin. The latch levers engage and restrain movement of the bolt member when biased in one direction. A spring means is provided for biasing the latch levers and master lever in one direction. The spring means is of novel construction having a frame portion and a plurality of spring arms formed integrally therewith. The spring arms are arranged in two banks with the spring arms of one bank extending towards and in staggered relationship with the spring arms of the other bank. A key guide member is rotatably mounted in the casing to receive a key which when rotated will pivot the latch levers (or the master lever) against the bias of the spring arms of the spring member to thereby move the latch levers out of restraining engagement with the bolt member. The pivot pin is journaled in opposite walls of the lock casing and the master lever is fixedly secured to the pivot pin.

ite Sttes Sallis et a1.

tet [191 1 LOCK MECHANISM [75] Inventors: Dwight L. Sallis, MenomoneeFalls;

Nathan L. Berkowitz, Milwaukee,

both of Wis.

[73] Assignee: Lock Corporation of America,

Milwaukee, Wis.

[22] Filed: Dec. 6, 1973 21 Appl. No.: 422,434

1,087,509 10/1967 Great Britain 70/DIG. 55

[111 3,85,420 1 1 Jan. 7, 1975 Primary ExaminerAlbert G. Craig, Jr.Attorney, Agent, or FirmMichael, Best & Friedrich [5 7] ABSTRACT A lockmechanism mounted in a casing including a bolt member slidably mountedin the casing for movement between lock and unlock positions. Aplurality of latch levers and at least one master lever are pivotallymounted in the casing by means of a pivot pin. The latch levers engageand restrain movement of the bolt member when biased in one direction. Aspring means is provided for biasing the latch levers and master leverin one direction. The spring means is of novel construction having aframe portion and a plurality of spring arms formed integrallytherewith. The spring arms are arranged in two banks with the springarms of one bank extending towards and in staggered relationship withthe spring arms of the other bank. A key guide member is rotatablymounted in the casing to receive a key which when rotated will pivot thelatch levers (or the masterlever) against the bias of the spring arms ofthe spring member to thereby move the latch levers out of restrainingengagement with the bolt member. The pivot pin is journaled in oppositewalls of thelock casing and the master lever is fixedly secured to thepivot pin.

15 Claims, 5 Drawing Figures LOCK MECHANISM BACKGROUND OF THE INVENTIONment for each latch lever. Such an arrangement is more costly tomanufacture because of assembly difficulties. The only one-piece typespring member known to applicant employs a plurality of spring arms allof which extend in a single direction. Such construction makes itdifficult, if not impossible, to provide a separate and independentbiasing force to each of the latch levers.

" The primary object of this invention is to provide a lock mechanismwhich is economical to manufacture and provides a smooth and preciseoperation.

SUMMARY OF THE INVENTION A lock mechanism mounted in a lock casingincluding a bolt member slidably mounted in the casing and a pluralityof latch levers pivotally mounted in the easing and adapted to restrainmovement of the bolt member when biased in one direction. A spring meansis provided for biasing the latch levers in said one direction. Thespring means is comprised of a spring member having a frame portion anda plurality of spring arms formed integrally therewith. The spring armsare arranged in two banks with the spring arms of one bank extendingtowards and in staggered relationship with the spring arms of the otherbank so that adjacent latch levers are separately and independentlybiased by alternately staggered spring arms.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a flat keylock which embodies the structure of the present invention;

FIG. 2 is an enlarged front view of the lock shown in DESCRIPTION OF THEPREFERRED EMBODIMENT Referring to the drawings in detail, the lockmechanism of the present invention is mounted in a metal case 10 havinga cover plate 12 and a pair of apertured attachment flanges l4, 14. Case10 also includes side walls l6, 18, 20, 22 and a rear wall 24.

The lock mechanism mounted in case 10 includes a bolt member 26 mountedfor sliding movement adjacent the rear wall 24 of the case and iscomprised of a plate portion 28, a locking nose portion 30 and a lockingbar or lug 32 fastened to plate portion 28 and extending at right anglesto the plane of plate portion 28. Plate portion 28 is also provided witha key actuation slot 31, as shown in FIG. 2.

The lock mechanism further includes a plurality of latch members 34a,34b, 34c, 34d, 34c and 34f, and a master lever 36'. The latch and masterlevers are. mounted in a stacked relationship as best shown in FIG. 3,

' Master lever 36 (FIG. 5) is mounted with a pressed fit on one end of apivot pin 38 and latch levers 34a34 are freely pivotally mounted on theremaining portion of pin 38. The entire sub-assembly of latch levers,master lever and'pivot pin is mounted in the case with the opposite ends40, 40 of pin 38 journaled in openings 42, 42 in cover plate 12 and rearwall 24 of lock case 10. '1

A spring member 44 of novel design is provided to bias the latch andmaster levers (downwardly as shown in FIGS. 2 and 3) to their lock orunlock positions. As best shown in FIG. 4, spring member 44 is of onepiece construction comprising a frame portion 46 hav ing integral .endextensions 47, 47 providing an essentially C-shape configuration and .aplurality of curved spring arms 48a, 48b, 48c, 48d, 48c, 48f and 48g.

Spring arms 48a, 48c, 48c and 48g, which form one bank of spring arms,extend from one end 47 of frame portion 46, and spring arms 48b, 48d and48f, which form a second bank of spring arms, extend from the other end47 of frame portion 46. The spring arms of the two banks are staggeredwith respect to each other, i.e., they extend towards each other withthe center lines of one bank of spring arms extending between the springarms of the other bank and vice versa. The free ends 49 of each springarm are of reduced width to make sure that each spring arm will makecontact with only a single lever.

It is important to note that in fabricating spring member 44 the metalbetween adjacent spring arms 48a -g is removed, leaving spaces 51between adjacent spring arms. Such removal of metal between adjacentspring arms reduces the amount of undesirable stresses left in thespring arms due to the rupture of the metal in the manufacturing processas compared to a spring con struction wherein the spring arms are formedby slitting or drawing the material without removal of any metal. In thelatter construction it is necessary to heat treat the material to stressrelieve the spring. No such heat treatment operation is required in themanufacture of the spring member of the present invention.

As best-shown in FIGS. 3 and 4, spring member 44 is mounted in case 10with the flat frame portion 46 and extensions 47 positioned flushagainst top wall 22 of the case with the spring arms thereon extendingdownwardly into contact with surfaces 50 and 52 of the master and latchlevers. With the specially designed spring member 44 of the presentinvention, each latch and master lever will be independently biased toits lock (or unlock position) by a singlespring arm. More specifically,spring arm 48a is in lbiasing contact with lever 34a, spring arm48b isin biasing contact with the next adjacent lever 34b, spring arm 48c isin biasing contact with next adjacent lever 34c, spring arm 48d is inbiasing contact with next adjacent lever 34d, spring arm 48c is inbiasing contact with next adjacent lever 348, spring arm 48f is inbiasing contact with next adjacent lever 34f, and spring arm 48g is inbiasing contact with master lever 36.

In the preferred embodiment spring member 44 is made of phosphorusbronze. Because of its structural configuration it lends itself to massproduction techniques of manufacture such as a progressivestampingforming process.

Referring again to master lever 36 and latch levers 34a34f, master leverhas a flat top surface 50 and latch levers have flat top surfaces 52 foruniform biasing engagement with the spring arms 48a-48g. Master lever 36has a cam surface 54 for actuation by a corresponding actuating surfaceon a master key (not shown). The masterlever36 also has an actuator bar58 which extends through aligned openings 60 in the latch members asbest shown in FIG. 2. Latch members 34a34f have cam surfaces 62 ofvarying configurations, each adapted for actuating contact with acorresponding actuating surface 64 on the shank of key 66 as best shownin FIG. 3. The bolt member 26 is actuated by actuating surface 65 at theend of key 66 which is adapted to engage slot 31 in plate portion 28 aswill be described in detail hereinafter. Each of such latch members isalso provided with a retaining slot 68 and a projecting lug 70 whichcooperate with locking bar 32 on bolt member 26 to retain the boltmember in either lock or unlock position.

A key guide member 72 is rotatably journaled in a hollow boss 74 oncover plate 12 and an opening 76 in rear casing wall 24. As best shownin FIG. 1, the end of locking bar 32 extends into a guide slot 78 incover plate 12 to provide a further guide means for the sliding movementof bolt member 26.

OPERATION FIGS. 1 and 2 show the lock mechanism in unlock position. Toactuate the lock from unlock" to lock position, key 66 is inserted intokey guide member 72 and then rotated 180 counterclockwise. During thefirst 90 of rotation, actuating surfaces 64 on key 66 will engage camsurfaces 62 on latch levers 34a-34f causing said levers to be pivotedupwardly against the bias of spring arms 48a-48f of spring member 44from the position shown in FIG. 2 to the position shown in FIG. 3. Suchupward pivotal movement of the latch levers to their release positionwill cause projecting lugs 70 thereon to move up and out of the travelpath of locking lug 32 on bolt member 26. Toward the latter part of thefirst 90 of key rotation and during the second 90 degrees of keyrotation actuating surface 65 at the end of key 66 will become engagedin slot 31 in the bolt member 26. With the latch levers actuated torelease position, the bolt member 26 will be free to slide (to the leftas viewed in FIGQ2) by the action of key surface 65 in slot 31. Therotation of the key will thus slide bolt 26 to its lock position shownin dotted lines in FIG. 2. As the key is rotated to its fully lockposition, locking bar 32 will move out from under projections 70 on thelatch levers, to thus allow such latch levers to pivot back to theiroriginal position under the bias of spring arms 48a-48f. The bolt member26 will be retained in its lock position by projections 70 on latchlevers 34a-34f, which as explained above will snap back behind lockingbar 32 as the key is rotated to its fully lock position. To actuate thelock mechanism from lock to unlock" position, the key is rotated 180clockwise. During such rotation the latch levers will again be actuatedupwardly to their release position to thus allow surface 65 on the keyto slide bolt 26 back to its unlock. position as shown in FIG. 2.

When a master key is employed to actuate the lock, such key (not shown)is provided with an actuatingsurface adapted for actuating engagementwith surface 54 on master lever 36. Actuation of master lever 36 againstthe bias of spring 48g will cause actuator bar 58 thereon to engage andactuate latch levers 34a-34f to release position to thus permitactuation of the bolt member 26.

It will be appreciated from the foregoing that by the use of a springmember 44 having oppositely extending staggered spring arms, each leverwill be separately and independently spring loaded with an equal biasingforce exerted on each lever. A smoother more precise operation results,making it more difficult to actuate the lock other than by itscorresponding pass key. As

- indicated previously, the above noted desirable biasing action isaccomplished with a one-piece spring member which can be fabricated byuse of mass production manufacturing techniques (requiring no heattreatment to remove undesirable stresses) and which can be readilyassembled with the other parts of the lock mechanism. Finally, it willalso be appreciated that by staking master lever 36 to pivot pin 38 andthen in turn journaling the pivot pin in the lock case, the master leverwill be firmly supported for pivotal movement in the lock case tothereby further enhance the precise operation referred to above.

We claim:

l. A lock mechanism mounted in a lock casing comprising:

a bolt member slidably mounted in the lock casing;

a plurality of latch levers pivotally mounted in the casing and adaptedto restrain movement of said bolt member when biased in one direction;

spring means for biasing said latch levers in said one direction, saidspring means comprising a spring member having a frame portion, aplurality of spring arms formed integrally therewith, said spring armsarranged in two banks with the spring arms of one bank extending towardsand in staggered, relationship with the spring arms of the other bank.

2. A lock mechanism according to claim 1 in which each of said latchlevers is separately and independently biased by a single spring arm ofsaid spring member.

3. A lock mechanism according to claim 1 in which said latch levers arearranged in a stacked relationship with adjacent latch levers separatelyand independently biased by alternately staggered spring arms of saidspring member.

4. A lock mechanism according to claim I in which said frame portion ofsaid spring member is positioned in such contact with one wall of thelock casing and said spring arms curving outwardly from the plane ofsaid frame portion into contact with said latch levers.

5. A lock'mechanism according to claim 1 in which said frame portion ofsaid spring'member has a pair of end extensions to provide anessentially C-shaped configuration with said spring arms of said springmember extending towards each other from said end extensions. 6. A lockmechanism according to claim 5 in which the free ends of said springarms are of a reduced width. 7. A lock mechanism according to claim 1 inwhich there are spaces between adjacent spring arms of each bank ofspring arms of said spring means.

8. A lock mechanism mounted in a lock casing comprising:

a bolt member slidably mounted in the lock casing and adapted formovement between lock and unlock positions;

a plurality of latch levers and at least one master lever pivotallymounted in the casing by means of a pivot pin, said latch levers adaptedto restrain movement of said bolt member when biased in one direction;spring means for biasing said latch levers and master lever in said onedirection, said spring means comprising a spring member having a frameportion and a plurality of spring arms formed integrally therewith, saidspring arms arranged in two banks with the spring arms of one bankextending towards and in staggered relationship with the spring arms ofthe other bank; and a key guide member rotatably mounted in said casingand adapted to receive a key which when rotated will pivot said latchlevers against the bias of said spring means to thereby move said latchlevers out of restraining relationship with said bolt member. 9. A lockmechanism according to claim 8 in which said pivot pin is journaled inopposite walls of said lock casing and said master lever is fixedlysecured to said pivot pin.

10. A lock mechanism according to claim 8 in which each of said latchlevers is separately and indepen- 6 dently biased by a single spring armof said spring member.

11. A lock mechanism according to claim 8 in which said latch levers arearranged in a stacked relationship with adjacent latch levers separatelyand independently biased by alternately staggered spring arms of saidspring member.

12. A lock mechanism according to claim 8 in which said frame portion ofsaid spring member is positioned in such contact with one wall of thelock casing and said spring arms curving outwardly from the plane ofsaid frame portion into contact with said latch levers.

13. A lock mechanism according to claim 8 in which said frame portion ofsaid spring member has a pair of end extensions to provide anessentially C-shaped configuration with said spring arms of said springmember extending towards each other from said end extensions.

14. A lock mechanism according to claim 13 in which the free ends ofsaid spring arms are of a reduced width. p

15. A lock mechanism according to claim 8 in which there are spacesbetween adjacent spring arms of each bank of spring arms of said springmeans.

1. A lock mechanism mounted in a lock casing comprising: a bolt memberslidably mounted in the lock casing; a plurality of latch leverspivotally mounted in the casing and adapted to restrain movement of saidbolt member when biased in one direction; spring means for biasing saidlatch levers in said one direction, said spring means comprising aspring member having a frame portion, a plurality of spring arms formedintegrally therewith, said spring arms arranged in two banks with thespring arms of one bank extending towards and in staggered relationshipwith the spring arms of the other bank.
 2. A lock mechanism according toclaim 1 in which each of said latch levers is separately andindependently biased by a single spring arm of said spring member.
 3. Alock mechanism according to claim 1 in which said latch levers arearranged in a stacked relationship with adjacent latch levers separatelyand independently biased by alternately staggered spring arms of saidspring member.
 4. A lock mechanism according to claim 1 in which saidframe portion of said spring member is positioned in such contact withone wall of the lock casing and said spring arms curving outwardly fromthe plane of said frame portion into contact with said latch levers. 5.A lock mechanism according to claim 1 in which said frame portion ofsaid spring member has a pair of end extensions to provide anessentially C-shaped configuration with said spring arms of said springmember extending towards each other from said end extensions.
 6. A lockmechanism according to claim 5 in which the free ends of said springarms are of a reduced width.
 7. A lock mechanism according to claim 1 inwhich there are spaces between adjacent spring arms of each bank ofspring arms of said spring means.
 8. A lock mechanism mounted in a lockcasing comprising: a bolt member slidably mounted in the lock casing andadapted for movement between lock and unlock positions; a plurality oflatch levers and at least one master lever pivotally mounted in thecasing by means of a pivot pin, said latch levers adapted to restrainmovement of said bolt member when biased in one direction; spring meansfor biasing said latch levers and master lever in said one direction,said spring means comprising a spring member having a frame portion anda plurality of spring arms formed integrally therewith, said spring armsarranged in two banks with the spring arms of one bank extending towardsand in staggered relationship with the spring arms of the oTher bank;and a key guide member rotatably mounted in said casing and adapted toreceive a key which when rotated will pivot said latch levers againstthe bias of said spring means to thereby move said latch levers out ofrestraining relationship with said bolt member.
 9. A lock mechanismaccording to claim 8 in which said pivot pin is journaled in oppositewalls of said lock casing and said master lever is fixedly secured tosaid pivot pin.
 10. A lock mechanism according to claim 8 in which eachof said latch levers is separately and independently biased by a singlespring arm of said spring member.
 11. A lock mechanism according toclaim 8 in which said latch levers are arranged in a stackedrelationship with adjacent latch levers separately and independentlybiased by alternately staggered spring arms of said spring member.
 12. Alock mechanism according to claim 8 in which said frame portion of saidspring member is positioned in such contact with one wall of the lockcasing and said spring arms curving outwardly from the plane of saidframe portion into contact with said latch levers.
 13. A lock mechanismaccording to claim 8 in which said frame portion of said spring memberhas a pair of end extensions to provide an essentially C-shapedconfiguration with said spring arms of said spring member extendingtowards each other from said end extensions.
 14. A lock mechanismaccording to claim 13 in which the free ends of said spring arms are ofa reduced width.
 15. A lock mechanism according to claim 8 in whichthere are spaces between adjacent spring arms of each bank of springarms of said spring means.